58 DACHNOWSKI: BOG VEGETATION AND PEAT SOILS 
9. Only a small amount of nitrogenous bodies can be extracted 
from peat by means of water. The relatively low free ammonia 
and the large amount of oxygen consumed indicate that the organic 
matter is not in an advanced state of decomposition. 
10. The solubility of a coarsely fibrous peat is less than that 
of peat in a finer state of division and more advanced stage of 
disintegration. This condition seems to point to the fact that 
the organic compounds arise mainly through the action of micro- 
organisms. Compounds associated with the decomposition prod- 
ucts of proteids by mineral acids, are here practically out of the 
question. 
I1. Little is known as to the chemical constitution of peat and 
of the transition and decomposition products of proteids and 
‘ carbohydrates arising in peat soils. Biochemical technique has 
not permitted, as yet, the analysis or the preparation of isolated 
peat soil constituents of comparative purity. They are undoubt- 
edly of access for chemical investigation and isolation. Known 
methods of investigation of proteids have been applied in the 
study of the decomposition products of organic compounds in soils. 
Schreiner and Schorey,* Jodidi,t and Robinsont have more 
recently isolated and identified a number of these bodies. 
In peat 
soils, 
however, the compounds are present in small amounts, the 
number of transition products is undoubtedly larger, and their 
effects upon living plants is as yet unknown. It is difficult to 
understand how a substance present in peat soils 
in such minute concentration that for ordinary c 
its influence is negligible, may nevertheless exert 
upon the growth of plants, 
or in bog water 
hemical analysis 
a profound effect 
It is not necessary to assume that 
can actually be absorbed and 
Chemical nature of soil organic matter. 
10, 
* Schreiner, O., and Schorey, E. C. 
U.S. Dept. Agr. Bur. Soils Bull. ye Ne 
Tt Jodidi, S.L. Organic nitrogenous compounds in Peat soils. Michigan Agr. 
Coll. Exp. Sta. Tech. Bull. 4. 1909. 
Robinson, C. S. Organic nitrogenous co 
: mpounds in peat soils. II, Michigan 
Agr. Coll. Exp. Sta. Tech. Bull. 7, 
IQIt. 
